Tert-Butylphenol

Oxidation of 4-methyl-2-tert-butylphenol (225, Scheme 57) by 2,3-di-chloro-5,6-dicyano-l,4-benzoquinone in methanol affords the dibenzofuran 228. The intermediate oxepinobenzofuran 226, as its valence isomer 227, undergoes nucleophilic attack by methanol and subsequent dienone-benzene rearrangement with the migration of the methoxy group. 

Specific compounds detected included propyl-3,4,5 trihydroxy benzoate, 2-tert-butyl-4-methoxy phenol, 2-tert-butylphenol, 2-(ert-butyl-4-methylphenol, and octyl-3,4,5-trihydroxybenzoate. 

A comparison of performance was carried out of DA-UVD and ELD for the determination of trace amounts of phenolic antioxidants, such as BHA (31), 2-tert-butylphenol, 2-tcrt-butyl-4-methylphenol, PG (33a) and OG (33b). The LOD were lower and the linearity ranges wider for ELD than UVD °. ... 

Dioctadecyl 3,5-di-tert-butyl-4-(hydroxybenzyl)phosphonate, 2 == 2,6-Bis(2-octadecyl)-4-methylphenol, 3 = 2,6-Di-tert-butylphenol, 4 = Pentaerythritol tetra-kis[3-[3,5-di-tert-butyl-4-(hydroxyphenyl)Jpropoinate], 5 = 2-tert-Butyl-4,6-dimeth-ylphenol, 6 = 2-tert-Butylphenol, 7 = 2,6-Diisopropylphenol, 8 = 1,3,5-Tris[3,5-di-tert-butyl-4-(hydroxybenzyl)]-2,4,6-trihydroxytriazine, 9 = l,3,5-Trimethyl-2,4,6-tris[3,5-di-tert-butyl-4-(hydroxybenzyl)]benzene, 10 == Methyl 3-[3,5-di-tert-hutyl-4-(hydroxyphenyl)jpropionate, 11 = Monoethyl 3,5-di-tert-butyl-4-(hydroxybenzyl)-vhosphonate, nickel salt, 12 = 2-tert-Butyl-5-methylphenol, 13 = 4,4 -Methylene-bis(2,6-di-tert-butylphenol), 14 = 2-tert-Butyl-6-methylphenol, 15 = Alkylated 2-tert-butyl-5-methylphenol, 16 = 2-tert-Butyl-4-ethylphenol, 17 = Methyl 3-[3-tert-butyl-4-(hydroxyphenyl)]propionate, 18 = 2,4-Di-tert-butylphenol. 

Hajek [57] studied the transformation of tert-butylphenols catalyzed by KSF and observed differences in reaction rate and product distributions tvhen comparing microtvave irradiation and conventional heating (Fig. 5.18). Several conditions tvere studied in the isomerization and transalkylation, including temperature and solvent effects, and it tvas concluded that different reaction rates and selectivity are a consequence of micro vave-induced polarization . In this vay, the absorbed 2-tert-butylphenol molecules are affected to a greater extent by micro vave irradiation... 

Fig. 5.18. Transformation of 2-tert-butylphenol conditions (B) A, total conversion (41) (2-TBP, ) catalyzed by Montmorillonite (42 + 43 +40) selectivity for phenol (40) ...

The reaction of phenol with terf-butanol in water at 250,275, and 300°C to produce 2-tert-butylphenol and 4-tert-butylphenol has been reported by Chandler et al. (Fig. 9.33). The mole fraction of product yields are shown as a function of time at each temperature in Figs. 9.34-9.36. When the products were subjected to NCW at 275°C, phenol was produced, indicating that the reaction is reversible. Small quantities (5%) of 2,4-di- fert-butylphenol are also formed. The reaction kinetics were described using a simple reaction network involving two reversible, first-order reactions (Fig. 9.37). 

Figure 9.35 Mole fraction product yields as a function of time for the reaction of phenol with tert-butyl alcohol in water at 275°C and 172 bar ( ) phenol (O) 2-tert-butylphenol (A) 4-tert-...

Figure 9.37 Model reaction network for the reversible alkylation reaction of phenol to form 2-tert-butylphenol and 4-tert-butylphenol in NO/V.

Figure 9.39 Arrhenius plotfortheforward and reverse rate constants forthe alkylation of phenol to form 2-tert-butylphenol in NCW ( ) ki ( ). ...

Rhodium-catalyzed allyl transfer to a,P-unsaturated ester proceeds in a conjugate manner (Scheme 5.39) [27]. Initially formed rhodium enolate would undergo P-hydride elimination followed by isomerization to afford a,p,y,5-unsaturated ester. 2-tert-Butylphenol is essential for smooth protonation to regenerate catalytically active rhodium alkoxide. 

Also obtained (by-product) by reaction of acetyl chloride on bromomagnesium 2-tert-butylphenolate in toluene at r.t. (<3%) [3348]. pale yellow oil [3346-3348] b.p. 87° [3347] ... 

Obtained by reaction of chloroacetyl chloride with dichloroaluminium 2-tert-butylphenolate or with trichloro (2-tert-butylphenoxy)tita-nium in toluene at r.t. (50% and 52% yields, respectively) [4564],... 

CH3)3Cv. COCHCl2 - Preparation by reaction of dichloroacetyl chlo-I jj ride on bromomagnesium 2-tert-butylphenolate... 

The sulfonation of 2-tert-butylphenol with chlorosulfonic acid has been studied kinetically the reaction mixture was demonstrated to contain 13 acids (derivatives of phenol, 2-tert-butylphenol, 4-tert-butylphenol and 2,4-ditert-butylphenol). The majority of the reactions gave first order rate constants and the operation of a two-phase reaction mechanism was discussed with reference to direct sulfonation, sulfate ester rearrangement and ipso sulfonation. 

Scheme 3.20 Enantioselective addition of 2-tert-butylphenol to ketenes...

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